The effect of a task-specific training on upper limb performance and kinematics while performing a reaching task in a fatigued state.

BACKGROUND: Fatigue impacts motor performance and upper limb kinematics. It is of interest to study whether it is possible to minimize the potentially detrimental effects of fatigue with prevention programs. OBJECTIVE: To determine the effect of task-specific training on upper limb kinematics and motor performance when reaching in a fatigued state. METHODS: Thirty healthy participants were recruited (Training group n = 15; Control group n = 15). Both groups took part in two evaluation sessions (Day 1 and Day 5) during which they performed a reaching task (as quickly and accurately as possible) in two conditions (rested and fatigued). During the reaching task, joint kinematics and motor performance (accuracy and speed) were evaluated. The Training group participated in three task-specific training sessions between Day 1 and Day 5; they trained once a day, for three days. The Control group did not perform any training. A three-way non-parametric ANOVA for repeated measures (Nonparametric Analysis of Longitudinal Data; NparLD) was used to assess the impact of the training (Condition [within subject]: rested, fatigued; Day [within subject]: Day 1 vs. Day 5 and Group [between subjects]: Training vs. Control). RESULTS: After the training period, the Training group significantly improved their reaching speed compared to the Control group (Day x Group p < .01; Time effect: Training group = p < .01, Control group p = .20). No between-group difference was observed with respect to accuracy. The Training group showed a reduction in contralateral trunk rotation and lateral trunk flexion in Day 2 under the fatigue condition (Group x Day p < .04; Time effect: Training group = p < .01, Control group = p < .59). CONCLUSION: After the 3-day training, participants demonstrated improved speed and reduced reliance on trunk compensations to complete the task under fatigue conditions. Task-specific training could help minimizing some effects of fatigue.

Systematic Review and Meta-analyses of Randomized Controlled Trials Comparing Exercise Loading Protocols With Passive Treatment Modalities or Other Loading Protocols for the Management of Midportion Achilles Tendinopathy.

Background: There is no clear consensus as to which intervention to prioritize for midportion Achilles tendinopathy (AT), although recent clinical practice guidelines have recommended eccentric exercises. Purpose/Hypothesis: The purpose of this study was to (1) compare exercise loading protocols with passive treatment modalities for the management of midportion AT and (2) compare different exercise loading protocols. We hypothesized that loading exercises would be associated with a greater decrease in pain and symptoms compared with passive treatment modalities but that no loading protocols would be associated with improved results. Study Design: Systematic review; Level of evidence, 1. Methods: Following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, we searched the MEDLINE, EMBASE, CINHAL, and Web of Science databases for randomized controlled trials (RCTs) and compared eccentric loading protocols with passive treatment modalities or different eccentric loading protocols as an intervention for midportion AT. A total of 5126 articles were identified after the initial search. After selection, the risk of bias (RoB) and the Grading of Recommendations, Assessment, Development and Evaluation approach were applied to pooled studies for quantitative analysis. The outcomes of interest were pain and function, which were measured using the visual analog scale and the Victorian Institute of Sport Assessment-Achilles scale. Mean differences (MDs) and 95% CIs were calculated using random effects (significant heterogeneity) or fixed effects (nonsignificant heterogeneity) inverse variance models. Results: In this study, 12 RCTs (N = 543 participants) were included, of which 2 had a high RoB and 10 showed some concerns of bias. Passive interventions resulted in greater pain reduction in the short term compared with eccentric loading protocols (n = 4 studies; n = 212 participants; pooled MD, 10.22 [95% CI, 2.18 to 18.25]; P = .01). For function, there was a nonsignificant trend in favor of eccentric loading in the short- (n = 3 studies; n = 144 participants; pooled MD, -7.91 [95% CI, -16 to 0.19]; P = .06) and midterm follow-up (n = 5 studies; n = 258 participants; pooled MD, -6.78 [95% CI, -14.23 to 0.68]; P = .07). Meta-analyses of RCTs comparing different types of exercise loading protocols showed no significant differences in the short, mid-, and long term with regard to pain and function. Conclusion: Our meta-analyses did not highlight the superiority of one treatment over another for midportion AT.